000
AXPZ20 KNHC 292123
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI MAY 29 2009

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...TROPICAL WAVES...
TROPICAL WAVE IS ALONG 95W FROM 02N-12N MOVING W 10 TO 15 KT. 
SCATTERED MODERATE TO ISOLATED STRONG CONVECTION IS NOTED EITHER 
SIDE OF THE WAVE AXIS PARTICULARLY TO NEAR THE INTERSECTION WITH 
THE ITCZ. THIS WAVE SHOWS UP WELL AS A HIGH AMPLITUDE MOISTURE 
SURGE ON THE UW-CIMSS TPW PRODUCT. BROAD CYCLONIC TURNING IS 
NOTED ON SATELLITE IMAGERY. THE GFS COMPUTER MODEL SUGGESTS THE 
DEVELOPMENT OF A LOW PRES IN THE VICINITY OF THE WAVE WITHIN 
ABOUT 48 HOURS.

...ITCZ...
THE ITCZ AXIS IS ALONG 08N78W TO 10N93W TO 07N105 TO 11N123W TO 
05N140W. SCATTERED MODERATE TO ISOLATED STRONG IS FROM 05N TO 
11N BETWEEN 89W AND 104W.  

...DISCUSSION...
A WEAK 1019 MB SURFACE HIGH CENTERED NEAR 25N127W COVERS THE 
NORTHERN WATERS N OF 16N AND W OF 110W PRODUCING MOSTLY FAIR 
WEATHER AND LIGHT WINDS. THE COMBINATION OF THIS HIGH WITH A 
WEAK SURFACE LOW PRES TROUGH ALONG CENTRAL MEXICO IS RESULTING 
IN FRESH NW WINDS N OF 23N WITHIN 90 NM OF BAJA CALIFORNIA 
COAST. LITTLE CHANGE IS EXPECTED IN THE WEATHER PATTERN DURING 
THE NEXT 24 HOURS AS THE HIGH PRES CENTER MOVES TO THE NW TO A 
POSITION NEAR 27N129W. A COLD FRONT HAS ENTERED THE NW CORNER OF 
THE DISCUSSION AREA. SW WINDS OF 20 KT ARE WITHIN 120 NM E OF 
THE FRONT. LONG PERIOD SWELLS FROM THE NW WILL FOLLOW THE 
FRONT...RAISING SEAS TO 12 FT EARLY SAT. A WEAKENING SURFACE 
TROUGH IS ANALYZED FROM 14N122W TO 06N129W. A FEW SHOWERS ARE 
EITHER SIDE OF TROUGH AXIS. 

ALOFT...AN UPPER-LEVEL LOW IS APPROACHING SOUTHERN CALIFORNIA. A 
WEAK UPPER-LEVEL TROUGH EXTENDS FROM THE LOW TO NEAR 22N125W.  
AN UPPER-LEVEL HIGH CENTERED NEAR 12N94 HAS AN ELONGATED RIDGE 
EXTENDING NWD ACROSS THE YUCATAN PENINSULA AND THE GULF OF 
MEXICO. THE RIDGE ALSO DOMINATES CENTRAL AMERICA AND WESTERN 
COLOMBIA. THIS UPPER-LEVEL FEATURE IS SUPPORTING THE CONVECTION 
MENTIONED IN THE ITCZ SECTION.  

$$
GR